Crusher blades of a sinter discharge part of a sintering machine

ABSTRACT

Crusher blades for the sinter discharge part of a sintering machine wherein a case encloses a rotating shaft and the blades extend outwardly from the case. Cooling medium flow passages are provided in the blades so that the cooling medium can be introduced through a supply pipe attached to the case, passed through the blades and discharged through an exhaust pipe also connected to the case.

United States Patent 1191 [111 3,843,064 Suzuki Oct. 22, 1974 [54] CRUSHER BLADES OF A SINTER 2,402,170 6/1946 Lund 241/67 x D SCHA G P OF A SINTERING 3,154,622 10/1964 Reinfeld et aI. 241/88 X MACHINE 3,398,900 8/1968 Guba 241/67 3,459,381 8/1969 Takahashi...... 241/67 [75] Inventor: Masao Suzuki, Aichi-Ken, Japan 3,662,961 5/1972 W lkowi k t 24l/6 X 1 3,680,799 8 1972 H 11 b k 241 67 X [73] Assignee: Nippon Steel Corporation, Tokyo, a er ac Primary Examiner-Granville Y. Custer, Jr. [22] Filed: July 10, 1972 Assistant Examiner-Howard N. Goldberg [211 Appl NO 270 508 Attorney, Agent, or Firm-T0ren, McGeady and Stanger [30] Foreign Application Priority Data July 12, 1971 Japan 46-51067 [57] ABSTRACT Crusher blades for the sinter discharge part of a sinter- [52] 11.8. C1 241/67, 241 /DIG. 13, 241/88.4, ing machine wherein a case encloses a rotating shaft 241/190 and the blades extend outwardly from the case. Cool- [51] Int. Cl. B02c 13/06, B02c 13/26 ing medium flow passages are provided in the blades [58] Field of Search 241/65 67, o that the c oling medium can be introduced through 241/DlG. 13, 189 R, 190, 86, 88, 88.4 a supply pipe attached to the case, passed through the blades and discharged through an exhaust pipe also [56] References Cited connected to the case.

UNITED STATES PATENTS 7 Claims, 7 Drawing Figures 249,910 11/1881 Dorrity 241/67 mums FIG 2 PATENTEU 0m 22 um IO 5 U JUU PME NTEUUCI 22 m4 Sammie CRUSIIER BLADES OF A SINTER DISCHARGE PART OF A SINTERING MACHINE The present invention relates to crusher blades of a sinter discharge part for the sintering machine.

As is well known sinters are crushed by crusher blades provided at the sinter discharge part of a sintering machine for crushing the sinters into grain sizes suitable for feeding into a blast furnace after sintering. The crusher blades in such an arrangement cooperate with a crushing plate A, usually positioned as shown in FIG. l, and, the blades C fixed on a crusher B of a rotating body, pass through gaps in plate A for crushing sinters supplied to that location.

Since lumps of sinters at a temperature range of 800 1,000C are crushed at the crusher part, each portion thereof is made of parts with high heat resistance and with high wear resistance, for example, a cast liner of high chromium content or of highcarbon content is used in the blades, or blades with hardened padding of tungsten or carbide type are used, and yet their serviceable life is quite limited.

There has been a recent tendency to adapt a sintering machine of large size for enhancing its productivity, and the crushing amount per each unit area of blades increasesin such sintering machine, and at a same time the temperature of sinters becomes higher, thus the temperature of blades reaches about 500C or higher, which lowers the hardness of the blades. Therefore, it is necessary to replace the blades every 40 to 50 days (during which 350 to 400 thousand tons are processed).

Thus, since periodical maintenance of sintering equipment must be made depending on the cycle of its serviceable life, it has been a big factor in remarkably reducing the maintenance time as compared to the operating time of a sintering machine.

The present invention was made to solve, in an advantageous manner, the disadvantages experienced in the past.

Accordingly the invention relates to a crusher blade of the sinter discharge part of a sintering machine, wherein a case encloses a rotating shaft and the-blades are secured to and extend outwardly from the case and each blade contains a dividing member. A cooling medium supply pipe and a cooling medium exhaust pipe are attached to the case so that the cooling medium can be passed through the blades flowing around the dividing member.

The present invention, as mentioned above, has such an arrangement of dividing plates within the case so that the cooling medium circulates through the case and the blades and then is exhausted, or such arrangement is provided by casting or by machine fabrication for forming the cooling medium flow-paths without the use of dividing plates within the case with the cooling medium supplied to one end of the row of blades and exhausted from the other end to achieve the cooling. For example, the present invention may be simply composed by attaching a cooling medium supply pipe and exhaust pipe to a case provided about a rotating shaft,

with the shaft rotating blades, insuch manner that the case is connected with the blades through the rotating shaft, thus the supply pipe, etc,. may be connected to the blades with a joint, etc,. when the blades rotate.

As the cooling medium, liquid, such as water, or a gaseous substance, such as air, can be used.

Now, examples of the present invention shall be explained,

FIG. 1 is a schematic drawing; of a crushing plate; FIG. 2 is a front elevational view with a portion thereof in section showing an example of the present invention; FIG. 3 is an enlarged view of the part of FIG. 2 shown bythe arrow A-A; FIG. 4 is a front elevational 'view with a portion thereof in section showing another example of the present invention; FIG. 5 is a front elevational view with a portion in section showing another example of the present invention; FIG. 6 is a schematic view illustrating the circulation of cooling medium; and FIG. 7 is a schematic view in cross section showing a portion of the FIG. 6 as marked by arrow B-B.

In the drawing, 1 is a rotating shaft. 2,2 are blades, 7 3,3" are dividing plates, is a case, 5 is a cooling mediumsupply pipe, 6 is a cooling medium discharge pipe, 8 is an exhaust tank, 9 is aplate, I0 is a joint, 11 represents blade edges, 12 represents holes or passages, 13 represents grooves, and 14 is an exhaust hole,

. EXAMPLE 1 In FIG. 2 and FIG. 3 dividing plates 3 are provided within hollow blades 2, 2 which are spaced at equal intervals on a rotating shaft 1, and the rotating shaft 1 is covered with a case 4 in such manner that the blades 2, 2' are connected to and extend outwardly from the case 4. The dividing plates 3 are connected to the shaft 1 and extend outwardly through the case 4 in the ho]- low blades 2,2 and terminate short of the inner surface of the blades at their radially outer ends. Dividing plates 3' are provided within the case 4 extending in the axial direction of the shaft between the shaft and the inner surface of the case as shown in the drawing, and a cooling mediumsupply pipe 5 and a cooling medium discharge pipe 6 are attached to the case 4 at one of its ends.

A cooling medium is supplied into the case 4 through the supply pipe 5. The cooling medium flows through the blades 2 passing around the dividing plates 3 within the blades 2 thus sufficiently cooling the blades 2. Gradually the cooling medium passes in a tortuous path through the blades 2 from the cooling medium supply end of the rotating shaft 1 to the opposite end, then as shown by the arrows in FIG. 2 the cooling medium reverses direction and flows back toward the supply end. In its return flow path, the cooling medium passes around the dividing plates within the blade 2'. After flowing through the blades 2, the cooling medium is discharged from the exhaust pipe 6' and through an exhaust tank 8.

In the drawing 9 is a plate, 10 is a joint, and 11 represents edges with blades 2, 2', thus the crusher rotates while the blades 2, 2 are cooled and lumps of sinters are crushed by the blades 2, 2 and the plate 9.

EXAMPLE 2 In FIG. 4 dividing plates 3 are provided within the hollow blades 2, 2 which are mounted on a rotating shaft 1 at equal intervals. The rotating shaft 1 is enclosed within a case 4 and the blades 2, 2' are attached to and extend outwardly from the case 4 so that the interiors of the hollow blades communicate with the interior of the case. As shown in the drawing a cooling medium supply pipe 5 is attached to the case 4 at one end tached to the case 4 at the other end of the-rotating shaft 1. Accordingly the cooling medium moves around along the dividing plates 3 as it flows through the blades 2, 2 and the case 4 and cool the blades. The cooling medium flows from the supply pipe 5 at one end to the exhaust pipe at the other end. Thus, the blades 2,2 are rotated as they are cooled and lumps of sinters are crushed by the blades 2, 2 and the plate 9. In the drawing is a joint.

EXAMPLE 3 In FIG. 5, FIG. 6 and FIG. 7, holes or passages 12 are machined within the blades 2,2 which are located at equal intervals on a rotating shaft 1 with the adjacent blades in the axial direction spaced 90 apart. Further, grooves 13 are machined in a' case 4 in such a manner that thegrooves are connected to the holes 12 in the blades 2, 2', and the blades 2, 2 and the case 4 are joined together by welding. As shown in the drawing a cooling medium exhaust hole 14 is provided in one end of the rotating shaft 1 and a cooling medium supply pipe 5 is provided within the hole 14 in a concentric arrangement for circulating cooling medium. Accordingly, the cooling medium circulate through a course consisting of the supply pipe 5 the hole 12 of the blade the groove 13 of the case the hole 12 of the next blade the groove l3 ofthe next case the hole 12 of the next blade the groove 13 of the next blade the hole 12 of the'blade and then to the exhaust hole 14 for discharge to the outside. The dotted lines 15 in FIG. 7 shows next blades. The blades 2, 2 are thus rotated while being cooled and lumps of sinters are crushed by the blades 2, 2' and the plate 9. In the drawing 16 is a liner with hardening padding.

Next, results of concrete performance by the crusher blades of the present invention shall be given below.

Performance 1 Crusher blades of the sinter discharge part of a continuous sintering machine having a production capacity of 8,400 t/D (tons/day) (DL sintering machine) were arranged as shown in the Example I, and 250 l/min. (liters/minutes) of water was passed as'a cooling medium to cool the blade liners which had been used at a temperature of about 500C. The liner was cooled and maintained at 200C and the sinters were crushed. Thus when about 1 million tons of sinters were processed, the blades were in such state as being sufficiently serviceable for continued use, and the durability of the blades which had been conventionally limited to a period for processing 350 to 400 thousand tons was remarkably enhanced.

Performance 2 Crusher blades of a sinter discharge part of a continuous sintering machine having a production capacity of 4,500 t/D (DL sintering machine) were arranged as in the Example 2, and 250 l/min. of water was made to pass as cooling medium, and the blade liners which had been conventionally maintained at a temperature of about 500C was cooled and maintained at 200C to crush sinters. When about 800 thousand tons of sinters had been processed the blades were in sufficiently serviceable condition for continued use. Thus the durability of the blades which had been conventionally limited to a processing period of 350 to 400 thousand tons was remarkably enhanced. I

As has beenexplained above, the present invention has such a distinguished effect that the serviceable life of the blades can be made remarkably longer and the operation of the equipment can be remarkably enhanced, thus productivity can be greatly improved. Llairaamw 1. In the sinter discharge part of a sintering machine comprising an axially elongated rotating shaft and crusher blades mounted on said shaft for rotation therewith for crushing sinters to a suitable grain size for feeding into a blast furnace, wherein the improvement comprises a case laterally enclosing said rotating shaft and secured thereon for rotation therewith, individual said blades attached to and extending outwardly from said case and spaced apart in the axial direction of said shaft, a cooling medium supply pipe connected to said case, a cooling medium exhaust pipe connected to said case, said case having at least one flow passage therethrough for the cooling medium, each said blade having a flow passage therethrough communicating with said at least one flow passage in said case for circulating the cooling medium in turn through said blades and case for maintaining said blades within a desired temperature range.

2. In the sintered discharge part of a sintering machine, as set forth in claim 1, wherein said case comprises a hollow body with its inner surface spaced radially outwardly from said shaft and forming an axially extending flow passage therebetween, dividing plates positioned within said case and extending in the axial direction of said shaft through said flow passage in said case from one end of said case to a transverse plane short of the other end thereof so that the flow passage is divided by said dividing plates into two sections in communication at the other end of said flow passage in said case, said blades being hollow, a dividing plate for each said blade secured at its radially inner end to said shaft and extending outwardly therefrom transversely of said shaft through the flow passage in said case into said blade in spaced relation from the inner surface of the hollow space within said blade and terminating at its radially outer end inwardly from the radially outer end of the hollow space within saidblade so that the flow passage within each said blade extends from the JPQfi blade t sasa to the ras fl y outer end of said dividing plate within said blade and then radially inwardly to the connection of said blade to said case.

3. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said blades being arranged in a number of axially spaced transverse planes along said shaft with said blades in each plane being spaced apart equiangularly from the adjacent said blades in the planes.

4. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said blades being arranged in a number of axially spaced transverse planes with said blades in adjacent planes being spaced apart relative to one another.

5. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said cooling medium supply pipe and said cooling medium discharge pipe are located at the same end of said case.

6. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said cooling medium supply pipe and said cooling medium discharge pipe are located at the opposite ends of said case.

7. In the sinter discharge part of a sintering machine, as set forth in claim 2, wherein said case is formed from a solid body having individual small flow passages machined therein in the axial direction of said shaft and extending between said blades spaced apart in the axial direction of said shaft, the cross-sectional area of said case extending transversely of the axis of said shaft being significantly greater than the cross-sectional area of said flow passages in said case, each said blade being formed from a solid body and having a continuous flow passage machined therein extending outwardly from each said blade from one said flow passage in said case to another said flow passage therein, and the crosssectional area of said blades being significantly greater than the cross-sectional area of said flow passages in said blades. 

1. In the sinter discharge part of a sintering machine comprising an axially elongated rotating shaft and crusher blades mounted on said shaft for rotation therewith for crushing sinters to a suitable grain size for feeding into a blast furnace, wherein the improvement comprises a case laterally enclosing said rotating shaft and secured thereon for rotation therewith, individual said blades attached to and extending outwardly from Said case and spaced apart in the axial direction of said shaft, a cooling medium supply pipe connected to said case, a cooling medium exhaust pipe connected to said case, said case having at least one flow passage therethrough for the cooling medium, each said blade having a flow passage therethrough communicating with said at least one flow passage in said case for circulating the cooling medium in turn through said blades and case for maintaining said blades within a desired temperature range.
 2. In the sintered discharge part of a sintering machine, as set forth in claim 1, wherein said case comprises a hollow body with its inner surface spaced radially outwardly from said shaft and forming an axially extending flow passage therebetween, dividing plates positioned within said case and extending in the axial direction of said shaft through said flow passage in said case from one end of said case to a transverse plane short of the other end thereof so that the flow passage is divided by said dividing plates into two sections in communication at the other end of said flow passage in said case, said blades being hollow, a dividing plate for each said blade secured at its radially inner end to said shaft and extending outwardly therefrom transversely of said shaft through the flow passage in said case into said blade in spaced relation from the inner surface of the hollow space within said blade and terminating at its radially outer end inwardly from the radially outer end of the hollow space within said blade so that the flow passage within each said blade extends from the connection of said blade to said case to the radially outer end of said dividing plate within said blade and then radially inwardly to the connection of said blade to said case.
 3. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said blades being arranged in a number of axially spaced transverse planes along said shaft with said blades in each plane being spaced apart equiangularly from the adjacent said blades in the planes.
 4. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said blades being arranged in a number of axially spaced transverse planes with said blades in adjacent planes being spaced 90* apart relative to one another.
 5. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said cooling medium supply pipe and said cooling medium discharge pipe are located at the same end of said case.
 6. In the sinter discharge part of a sintering machine, as set forth in claim 1, wherein said cooling medium supply pipe and said cooling medium discharge pipe are located at the opposite ends of said case.
 7. In the sinter discharge part of a sintering machine, as set forth in claim 2, wherein said case is formed from a solid body having individual small flow passages machined therein in the axial direction of said shaft and extending between said blades spaced apart in the axial direction of said shaft, the cross-sectional area of said case extending transversely of the axis of said shaft being significantly greater than the cross-sectional area of said flow passages in said case, each said blade being formed from a solid body and having a continuous flow passage machined therein extending outwardly from one of said flow passages in said case to the radially outer end of said blades and then reversing direction and extending inwardly to another said flow passage in said case for affording a continuous flow passage to each said blade from one said flow passage in said case to another said flow passage therein, and the cross-sectional area of said blades being significantly greater than the cross-sectional area of said flow passages in said blades. 